No, but the code is here for anyone to use if they wish.

Merged now. https://gitlab.haskell.org/ghc/ghc/commit/c2455e647501c5a382861196b64df3dd05b620a2

Responded to new comments now.

https://gitlab.haskell.org/ghc/ghc/merge_requests/106

I applied Simon's suggestions apart from the one about TcGblEnv which I don't think made the code much clearer as it then wasn't obvious which bits to extract from the TcGblEnv to combine together with the other TcGblEnv in order to get the correct result.

I put the patch on gitlab: https://gitlab.haskell.org/ghc/ghc/merge_requests/49

This patch is now at https://gitlab.haskell.org/ghc/ghc/merge_requests/16

CI passes: https://gitlab.haskell.org/mpickering/ghc/pipelines/460

• remove merge artifacts

I rebased. Last night I tested that the default build works correctly, I fixed the binary-dist target so that it doesn't build haddock with Stage2 libraries and also verified that test works correctly.

• Define and use stageLibaries
• Resolve some more stage confusion
• fix build
• Make things even more consistent
• docs
• Cleanup
• Remove tabs
• Andrey's suggestions
• Implement the finalStage build option
• Note about libffiContext
• Fix lint
• Alp comments
• Use stage1 haddock

• Alp comments

@snowleopard I implement the finalStage solution that @alpmestan suggested. It turned out quite nicely and meant we could remove the stage1Only option.

• Implement the finalStage build option
• Note about libffiContext
• Fix lint

In D5458#150798, @alpmestan wrote:

So I think that is all the packages?

There's a trivial way to find out, ls _build/stage2/lib/package.conf.d/.

In D5458#150792, @alpmestan wrote:

This is looking pretty good. Besides Andrey's outstanding question, I made a suggestion and have one request to add a TODO.

Can you clarify how far this gets you? I don't think the flavour matters much, so I won't ask whether you've built with different flavours. You said you get as far as building a working stage 3 compiler, right? And if you make stagePackages return the whole series of packages that a bindist would ship with, does that work too? Maybe you can just borrow that list from stage2Packages (or alternatively stagePackages Stage2)?

• Andrey's suggestions

I completed a stage3 build from a clean tree successfully with this patch and a modified UserSettings.hs. Another review @snowleopard would be good seeing as it also involved some more radical changes now.

• Remove tabs

• Make things even more consistent
• docs
• cleanup

Still broken in fact, see Trac #16069 for where the problem lies.

I think I fixed things up now. @alpmestan can you review?

• fix build

@DavidEichmann I think it will be much easier if you rebase the patch? This review cycle has been going on for a very long time now.

In D5458#150586, @harpocrates wrote:

I think that stageLibraries also needs to be used in configurePackage to make sure you end up needing packages from the right stage. That occurs here: https://github.com/ghc/ghc/blob/ed69f8bd1fd4b84b62bb4f10eef7f76e537be07b/hadrian/src/Hadrian/Haskell/Cabal/Parse.hs#L116. Note that this is already wrong for stage 2 thereby preventing me from building Haddock >:(.

Still not ready. There is a problem with packageDbPath resolving to the wrong thing in some places. This stems from the fact that packageDbPath used to have a call to min in which clearly does the wrong thing and relies on the fact that we didn't used to build any libraries with the stage2 compiler. I haven't managed yet to work out how to precisely fix this though.

Thanks Andrey, I managed to apply your suggestions and things appear to work smoothly still. I'll try a clean rebuild overnight.

• Define and use stageLibaries
• Resolve some more stage confusion